Canine influenza – or dog flu – has been diagnosed in dogs for several years. But a new strain of canine influenza called H3N2 has been found in more than 25 states since April 2015. In Chicago, this novel (or newly appeared) influenza virus sickened more than a thousand dogs during the first outbreak in the United States. Now, Public Health – Seattle & King County veterinarian Beth Lipton thinks that we may have found cases here in King County. Public Health Insider talked to her to find out more.

What makes you suspect that this new strain of canine influenza virus is in King County? During the month of December 2015, dogs at an area boarding and dog daycare facility began getting sick with respiratory symptoms, primarily cough. The facility owner estimates about 80-90 dogs got sick. The facility self-closed and implemented isolation procedures to help contain the outbreak. Recently laboratory tests from two dogs that had contact with an ill dog who’d been at the facility were found to be positive for H3N2 canine influenza.

The H3N8 strain of canine influenza has been in the U.S. since 2004. Why is this new H3N2 strain of particular concern? While it’s been found in parts of Asia, canine influenza H3N2 is new to the United States. Since canine influenza virus H3N2 is a novel virus, all dogs, regardless of breed or age, are at risk of infection when first exposed. The virus is highly contagious and dogs get sick easily. In Chicago last year, thousands of dog owners brought their dogs to the vet, overwhelming their offices. Because it’s so contagious, if boarding facilities, shelters, and doggie day cares experience an outbreak they may need to temporarily close, which would be highly disruptive.

What are the signs and symptoms? Symptoms include cough, runny nose, and/or fever. Sick dogs may be lethargic. Dogs can come down with the flu within 24 hours of exposure. Some dogs don’t show symptoms, but are able to infect other dogs for weeks. This strain of canine influenza isn’t particularly deadly, but can cause a secondary infection like pneumonia, which can kill dogs.

How does it spread? Just like with human flu, the virus can be spread by direct contact, contaminated objects such as hands, surfaces, clothing, etc., and through droplets in the air, which may travel up to 20 feet or more. The virus can live in the environment for about 2 days and on hands and on clothing for up to 24 hours. If the virus enters a kennel or other closed group, a high percentage of the dogs become infected, and most will be symptomatic.

Once this virus gets a foothold in the community, there is a risk of continued transmission, especially at places where dogs congregate such as dog parks/beaches, dog daycare and boarding facilities, grooming facilities, and veterinary clinics. Dog owners whose dogs are coughing or showing other signs of respiratory disease should not expose their dog to other dogs, and should contact their veterinarian. Early veterinary evaluation is crucial to identifying and stopping potential outbreaks.

Does this strain of canine influenza infect humans or other animals? No human infections with canine influenza have ever been reported. In Asia, canine influenza virus H3N2 has been reported to infect cats, although transmission to cats in the US has been extremely rare. There is some evidence that guinea pigs and ferrets can become infected.
What is Public Health’s Zoonotic Disease program’s role in monitoring this disease? Even though this is a disease that does not make people sick, our job is to make sure that the pet businesses we regulate know the best ways to prevent an outbreak in their business and the community. Prevention steps include proper infection control, watching dogs carefully for signs of flu, and immediately isolating any dog that has symptoms. We also work with community veterinarians to increase their awareness and help educate the public about prevention.

Where can I get more information about canine influenza? A great website that has information for dog owners is www.doginfluenza.com. If you have a dog, check it out! And be on the lookout for coughing, runny nose, or fever in your dog. If you see those symptoms, keep your dog away from other dogs, and call your vet right away.